Transcript Commercial Hot Water Systems

Energy Rating Index
Performance Path
Speaker Name
Speaker Affiliation
Goals of
the
Concept
Increase compliance for residential
energy codes
Increase building energy savings through
increased compliance
Complement existing performance-based
residential efficiency programs
Create cost-effective retrofit and new build
strategies to exceed minimum code
requirements
Overview of the ERI
Performance Path
ERI Performance Path
• Additional option for IECC
compliance
• Target ERI score is met
through a wide range of
performance options
• Requires builders to achieve
the mandatory code
requirements of the 2015
IECC and comply with
minimum insulation and
window envelope
performance requirements
of the 2009 IECC
Mandatory Requirements
 2015 IECC provisions
including:
 Section R402.4 Air
Leakage
 Section R403 Systems
 Section R403.5 Service
Hot Water Systems
 Section R404 Electrical
Power and Lighting
Systems
 Building Envelope
requirements of the
2009 IECC
States and jurisdictions can specify which
qualifying ERI method they will use
RESNET HERS
Index is the
existing
compliance
ERI method
• Is nationally recognized
• Based on ANSI RESNET Standard 3012014
• To date, over 1.5 million homes have
been rated in the US under the
RESNET standards
What is a HERS Index and Score?
A scoring system
established by
RESNET based
off of the 2006
IECC
The scale is
based on a
100 – 0 index
A home based on
the 2006 IECC
scores a HERS
Index of 100
A score of 0 is
equivalent to a
net zero home
2015 IECC Target ERI Scores
The ERI score is defined as a
numerical score where 100 is
equivalent to the 2006 IECC
and 0 is equivalent to a netzero home. Each integer value
on the scale represents a one
percent change in the total
energy use of the rated design
relative to the total energy use
of the ERI reference design.
2015 IECC Target ERI by Climate Zone
Climate Zones 1-2: 52
Climate Zone 3:
51
Climate Zone 4:
54
Climate Zone 5:
55
Climate Zones 6:
54
Climate Zones 7-8: 53
What is included in an Energy Rating?
Energy ratings are based on a number of variables
including the type and efficiency of each of the
following:
 Equipment
 Appliance upgrades
 Exterior walls (both above and below
grade)
 Floors over unconditioned spaces
(such as garages or crawlspaces)
 Ceilings and roofs
 Attics, foundations and crawlspaces
 Windows and doors, vents and ductwork
 HVAC and water heating systems
 Air leakage of the home
 Leakage in the heating and cooling
distribution system
Average HERS Index by Climate Zones
March 2012 – March 2014
Over 240,000 homes
between 8 climate
zones have been
rated using the HERS
Index and have a
weighted average
score of 63.55.
Benefits of the Energy Rating
Index Score Option
Benefits of the Energy Rating Index
Score Option
From a
Builder’s
Perspective
• Lower First Costs
• Building Innovation
• Increased Flexibility in
Compliance
From a
Consumer’s
Perspective
• Utility Bill Savings
• Resale Value
• Comparison Shopping for
Beyond Code Minimum Homes
Cost Effectiveness of Using the ERI to
Comply with the 2015 IECC
A study by the Florida Solar Energy Center compared homes
configured to comply with the ERI performance path provisions of
the 2015 IECC to homes configured to comply with the 2012 IECC.
The study found
Life-cycle cost
Annual savings of
that in all cases,
savings, averaged
the 2015 IECC ERI
compliance with
across climate
performance path,
the ERI
zones, is $12,784
averaged across
performance path
for the 2015 IECC
climate zones, is
of the 2015 IECC is
ERI performance
$468
cost-effective
path
2015 IECC Improvement Costs
Incremental improvement costs
of improving 2012 IECC homes to
comply with 2015 IECC ERI
criteria were determined using
methodology for evaluating cost
effectiveness of retrofits for
DOE’s Building America program
Most Common
Efficiency Improvements
100% HighEfficiency
Lighting
Higher
Efficiency
Heating,
Cooling and
Water
Heating
Equipment
Duct Systems
Inspected
and Tested to
Meet
Improved
Performance
Enhanced
Envelope
Efficiencies
Energy Star
Refrigerators,
Dishwashers
and Clothes
Washers
Economic Analysis
Life-CycleCost
Analysis
Economic
Parameters
• Based on 30 year life-cycle-cost
analysis
• Section 4.6 of ANSI/RESNET 301-2014
• Includes replacement costs and
maintenance fraction
• 25% income tax rate
• 4% property tax rate
• Property assessment ratio of 80%
• Most recently published energy prices
Case Studies
Residential Green Building
Code
City of Santa Fe
Required HERS scores built
on levels set in National
Green Building Code
Applies to all new single
family homes, attached
and detached
Homes 3,000ft² or less
required to achieve HERS
score of 70 or less
HERS scores for homes
greater than 3,000 ft²
tiered based on home size
How does a home in Santa
Fe receive a HERS score?
HERS scores determined
by certified HERS rater
that has completed
RESNET training and Santa
Fe training courses
Preliminary HERS based
on building plans is
submitted with residential
checklist to obtain
building permit
Final HERS prepared once
home is nearly complete
and assumptions in
preliminary HERS have
been verified
A report that reflects the
final HERS score is posted in
the window of the rated
home prior to the issuance
of a Certificate of Occupancy
and may only be removed
by the first occupant
Santa Fe Best Practices
• Requiring that all new construction receive a HERS
rating during the initial stages of the program
familiarized builders with the process of obtaining
a target HERS score.
• No initial HERS score allowed builders to learn
through trial and error how to achieve low ratings
Building department personnel were sent to HERS
trainings to ensure awareness of the program.
• The program is set up to focus primarily on
elements of the building envelope.
• Building inspectors and HERS raters work together
to achieve maximum efficiency in new residential
construction.
• HERS raters also work closely with one another to
ensure consistency and credibility within the Santa
Fe HERS community.
• Additional training required for HERS raters to
ensure quality assurance is maintained
Best practices have led to:
 A realistic set of scores for
the jurisdiction
 An increase in quality of
construction
 Construction practices
that reflect unique needs
of the city
 An increase in support for
the program from the
building community
 Competition among
builders
 An increased in use of
energy efficient products
and technologies
Resources
RESNET
• Gather HERS
information
• Identify states and
jurisdictions using
HERS Index
• Find a local RESNET
HERS rater
www.resnet.us
www.hersindex.com
Energy Rating Index Fact Sheets
Six informational fact sheets are available
•
•
•
•
Overview of the ERI Performance Path in the 2015 IECC
Benefits of the Energy Rating Index Score Option
Frequently Asked Questions
Cost Effectiveness of Using the ERI to Comply with the
2015 IECC
• Implementation Guidelines for the ERI Performance
Path
• ERI Performance Path Score Alternatives
• Case Studies: Incorporating the HERS Index into an
Energy Code
Questions?